Long-term results of 292 CarpoFit®-joint replacements for trapeziometacarpal osteoarthritis: a prospective cohort study with a 10-year follow-up.

We report a prospective consecutive series of CarpoFit® (Implantcast, Buxtehude, Germany) trapeziometacarpal prostheses used between 2006 and 2014 for 292 patients with stage I-III trapeziometacarpal arthritis who remained symptomatic after conservative treatment. Patients were assessed at 3 months, 6 months and 1 year postoperatively for thumb movement, pinch strength and by validated patient-derived outcome scores and radiographs. Follow-up at 5 and 10 years was by outcome scores alone. Complications and revisions were recorded. Of the patients, 91% were either satisfied or very satisfied with their treatment at 10 years. Pain relief and functional outcomes were significantly improved within 3 months. Results were sustained during the entire observation period. The implant survival was 95% after 10 years. Prosthetic arthroplasty is a reliable treatment option for trapeziometacarpal osteoarthritis and the CarpoFit® prosthesis has excellent long-term results for patient satisfaction, functional scores and implant survivorship.Level of evidence: III.

Magnetic Resonance Imaging of the Axial Skeleton in Patients With Spondyloarthritis: Distribution Pattern of Inflammatory and Structural Lesions.

PURPOSE: Spondyloarthritis is a chronic inflammatory disorder of the musculoskeletal system driven by systemic enthesitis and typically involving the axial skeleton, ie, the spine and the sacroiliac joints. The purpose of this study was to assess the distribution pattern of inflammatory and structural magnetic resonance imaging (MRI) findings in spondyloarthritis. METHODS: Retrospective study of 193 patients with axial spondyloarthritis who received MRI of the spine and the sacroiliac joints. We quantitatively assessed inflammatory and structural lesions using established MRI-based scoring methods. The significance of the differences between gender, HLA-B27 status, and spine and sacroiliac involvement was determined. RESULTS: In total, 174 patients (90.2%) showed a sacroiliac involvement and 120 patients (62.2%) a combined involvement of the sacroiliac joints and the spine. An isolated sacroiliac involvement was found in 54 patients (28.0%) and an isolated spine involvement in 19 patients (9.8%). The sacroiliac joint was significantly more involved in men than in women (P < .01), and men had significantly higher scores for structural lesions (P < .001). The subgroup of HLA-B27-positive patients showed a significantly higher percentage of sacroiliac involvement compared with HLA-B27-negative patients (P < .05). CONCLUSIONS: Spondyloarthritis is a systemic disorder predominantly involving the sacroiliac joints. However, the entire axial skeleton may be affected. In particular, HLA-B27-negative women show atypical manifestations without sacroiliac involvement. Magnetic resonance imaging in spondyloarthritis should cover the entire axial skeleton, ie, sacroiliac joints and the spine to meet the pathophysiology of this disorder and capture the true extent of inflammatory and structural lesions.

Pathophysiological advantages of rinsing-suction-reaming (RSR) in a pig model for intramedullary nailing.

Although reamed intramedullary nailing has been one of the greatest advances in modern fracture care, the concomitant increase in medullary cavity pressure leads to intravasation of bone marrow content into the blood stream, an effect that can evoke serious systemic reactions. A newly developed rinsing-suction-reamer (RSR) was able to substantially reduce the pressure and bone marrow intravasation content during experimental femoral nailing. We investigated the pathophysiological effects using the RSR, testing the hypothesis that by reducing marrow fat embolization, RSR would also reduce the activation of coagulation compared with the universal AO-Reamer (AOR) and comparable to external fixation. Twenty-two pigs were treated with either simulated external fixation or reamed femoral nailing using AOR or RSR. During surgery, the intramedullary pressure was measured and intravasation of medullary material was quantified. After surgery, the pigs were kept anaesthetised and monitored for 6 h. At defined intervals, serological, hematological, and hemodynamic parameters were evaluated. The RSR was significantly superior when compared to AOR with regard to the generation of intramedullary pressure and fat embolization; however, with external fixation the values were even lower. The evaluation of other parameters revealed no clear differences between the two reamers and the external fixator. The pig model showed that RSR led to a significant reduction of the intramedullary increase in pressure and fat intravasation compared to AOR. Although the reduction of fat embolism by RSR is not associated with pathophysiological changes, RSR can have advantages for the treatment of femoral fractures.

Effectiveness of hydroxyapatite-vancomycin bone cement in the treatment of Staphylococcus aureus induced chronic osteomyelitis.

In the field of local application of antimicrobials, a number of novel drugs and/or new drug delivery systems have been developed in recent years. The present study aimed to investigate hydroxyapatite cement (HAC) as a carrier for vancomycin in the treatment of chronic osteomyelitis due to Staphylococcus aureus strains with various mechanisms of resistance. The release of vancomycin from standard test cylinders was determined in vitro and the efficacy of the delivery system was measured in vivo using a rabbit model of chronic osteomyelitis. First, powdered HAC was mixed with vancomycin at 80, 160 and 240 mg/g. After hardening, formed cylinders were eluted in phosphate buffer and antibiotic release was measured by agar diffusion. High levels of release (1512+/-318 to 1937+/-336 microg/ml) were obtained for 12 to 20 days depending on the dosage of vancomycin. Additionally, bone infection was induced in the tibia of 30 New Zealand white rabbits by injecting either a methicillin-resistant S. aureus strain (MRSA) or a S. aureus strain with a small colony variant (SCV) phenotype. After 3 weeks (chronic infection), all animals were treated by debridement. Moreover, group 1 (challenged with SCVs) and group 2 (challenged with MRSA) were treated by filling the marrow with HAC alone, whereas in groups 3 (SCVs) and 4 (MRSA) the marrow was filled with HAC/vancomycin (160 mg/g). After 6 weeks all animals were sacrificed. At 3 weeks, pathogens were detected in 24 of 30 animals. All swabs of the control groups, positive for S. aureus on day 21, were also positive on day 42 and S. aureus strains recovered were shown to be clonal to the strains used for induction of osteomyelitis. By contrast, no growth was found in the treatment group following 7 days of incubation in BHI bouillon. HAC/vancomycin-treated animals showed no histological evidence of infection on day 42. In the other groups, different stages of chronic osteomyelitis were found histologically. No local or systemic side effects due to HAC or vancomycin were seen. HAC is an effective carrier material for antibiotic compounds even in refractory infections due to MRSA or S. aureus SCVs.

Suspected central anticholinergic syndrome in a 6-week-old infant.

A 6-wk-old male infant became unresponsive after an uneventful general anesthetic for hernia repair. His symptoms were consistent with central anticholinergic syndrome. He appeared to awaken after treatment with IV physostigmine in a dose of 0.04 mg/kg. Because of the recurrence of sedation, a second physostigmine infusion was administered, which again led to transient arousal. Finally, the patient awoke spontaneously after 24 h and recovered uneventfully.

Rinsing-suction reamer attenuates intramedullary pressure increase and fat intravasation in a sheep model.

BACKGROUND: Reamed intramedullary nailing causes an increase of intramedullary pressure. A new rinsing-suction reamer (RSR) can reduce this problem, and it was evaluated in animal experiments in comparison with the AO reamer (AOR) to see its effects on intramedullary pressure and fat intravasation. METHODS: Reamed intramedullary nailing was performed in 14 sheep using the RSR or AOR. The following parameters were evaluated: intramedullary pressure, hemodynamics, blood tests, lung histology, and radiographs of the femur that was operated on. RESULTS: Intramedullary pressure during reaming was significantly (p < 0.001) lower with RSR (9 mm, 34 mm Hg; 9.5 mm, 4 mm Hg; 10 mm, 1 mm Hg) than AOR (9 mm, 750 mm Hg; 9.5 mm, 292 mm Hg; 10 mm, 138 mm Hg). There was a significantly (p < 0.05) higher increase of pulmonary resistance in AOR (from 144 +/- 84 dyne x s x cm to 391 +/- 169 dyne x s x cm) than in RSR (from 137 +/- 51 dyne x s x cm to 258 +/- 105 dyne x s x cm) after nailing and less intravenous fat measured in RSR (0.9; AOR, 2.9; p < 0.05) at all stages of reaming, at nail insertion (RSR, 0.3; AOR, 2.7; p < 0.05), and 30 seconds after nail insertion (RSR, 0.2; AOR, 1.1; p < 0.05) proved by the Gurd test. Pco2 increased (p < 0.05) in AOR (AOR, 36 +/- 5 vs. 40 +/- 7 mm Hg; RSR, 33 +/- 4 vs. 32 +/- 3 mm Hg) and pH dropped significantly (AOR, 7.49 +/- 0.06 vs. 7.45 +/- 0.05; RSR, 7.53 +/- 0.04 vs. 7.54 +/- 0.04; p < 0.05). Semiquantitative histologic analysis proved a significant higher pulmonary fat load in AOR (13.1 +/- 13.4) versus RSR (3.9 +/- 1.5, p = 0.00002). CONCLUSION: Because we found only a minimal increase of the pulmonary arterial pressure as a sign of pulmonary embolism, we conclude that by using the RSR, the systemic side effects caused by intravasation of medullary content during reaming could be reduced as far as possible.